Vertical incinerator grate



C. H. BROOKE VERTICAL INCINERATOR GRATE Nov. 11, 1958 3, Sheets-Sheet 1Filed Sept. 21. 1954 Hill 1 PM H E MR m R M BV r E K R u w c F H M Nov.11, 1958 c. H. BROOKE VERTICAL INCINERATOR GRATE 3 Sheets-Sheet 2 FiledSept. 21, 1954 lll CLARKE H. BROOKE INVENTOR.

Nov. 11, 1958 c. H. BROOKE 2,359,743

. VERTICAL INCINERATOR GRATE Filed Sept. 21. 1954 Q :s Sheets-Sheet sFIG. 8

jfl FIG-9 CLARKE H. BROOKE INVENTOR.

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United States Patent VERTICAL INCINERATOR Clarke H. Brooke, Seattle,Wash, prlis fis ep ember 2 A er a 1Nq- 5w:

' 2 Claims. (or. 126-463) My inyention relates to grate construction,and, more particularly, to a cast iron, vertical. incinerator grate.Provision is made to prevent accumulation, of ashes, on the face of thegrate by; having. precipitous walls and the grate is formed to.facilitate melding of the same and to simplify its installation invarious types of iniasr-a q A vertical grate has advantages overtheconventional horizontal grate, particularly in incineratorsfwhere.considerable ashes are allowedv to accumulate in, the, bottom Of theincinenator between cleanings, and; the furnacev is frequently.overloaded, One difficulty with horizontal grates is deterioration from.having liye coals lying on the, su nfaee. On the other hand/thehorizontal grate is less efficient if a layer of ashes and spot is left.on

the, grate. For these reasons, there has been. a more onless, recentdevelopment in the use. of verti cal grates a ea ears nd heat sea i thisp c tion has several advantages oyer thoseprevious ly; found cu -themarket. Prior grates with sloping facesl have ha d the characteristic offormingv a surface for the collection ofmaterjal, particularly ashes,which reduced the efficieney of the air openings orentirely closed them.

Among. other disadvantages, these grates have had irregular. shapes inrear elevation so as. to, make it diflicult for faunason to. brickaround, the grate and. some have had difficult structures to mold. i

The objectives, of my inyention include, therefore: to devise a verticalgrate constructed so as, t red-uce to a minimum the obstruction of theair openingswith ashes and other debris, to. devise a vertical gratefacilitating molding, andinstallation of the same, to provide a grateadaptable to various types and sizes of, incinerators and to improvetheconstruction of. the air passageways in such ra es.-

Ihe. invention will be best understood, together with additionalobjectives and; advantages over previous constructio-ns, from a readingof the following description, when read with reference to the drawings,in which:

Figure l is a front elevational view of a specific embodiment of myincinerator grate;

Figure 2 is asectional. view taken. on line 2 -2 of Figure 1;

Figure 3 is a sectional view taken on line. 3 -3 of Figure l Figure 4'is. a perspective. view ofyone type of an. in-

' cinerator;

ingsof the grate and having washers and nuts 42 abutting r P t nt d.New. 1 .55

The incinerator grate 10 may be installed in various types ofincinerators, one formed of brick construction being. shown in. Figure4, and, the. use. of a steel drum being suggested in. Figure, 7. Theincinerator may be of various sizes including largev incinerators forpublic buildings, manufacturing concerns, grocery stores, and the. like,and also including small. incinerators for households, in the smallerincinerators, i. e., for household use, a, single grate. may be used. ofsmall size, as for example, an 18 inch high 4 inch 1. D., 16 pound grateoperative with a maximum incinerator capacity of approximately 12.4cubic feet. A large size would be 18 inches high, 7 /2 inch 1. D. grate,weighing approximately 38 pounds, and operative singly withapproximately 48 cubic feet of capacity. In large incinerators, may bedesirable to. use more" than, one grate, as. suggested in Figure 5, orto use superposed grates as shown in, Figure 8.

Referring toFigure 1, the grate 10 is. preferably molded as a one pieceunit from. cast iron, as experience has shown that this material has thelongest life, againstrusting and deformation from heat, of materials ofeconomical manufacture. No machine work is required after casting. Theback 12. is completely, open, and the inner walls 1 4 diy erge from, theforwardside to. rear side 12 so that the mold may be readily removed. Itwill be understood that thisleads to economical manufacture of the unitbecause in more closed bodies itis necessary, to use a core which isexpensive to make and difficult to remov C ma n ne, o th mos co ly options in a foundry.

Referring toEigure 1., side walls 20, 22 are substantially parallelandthe bottom edge 24 lies in a plane normal to the side walls. Likewisetop wall. 26 lies in a P 21? norm l t sid wal 0.. 2 ex ep o he e i v dtopcornersZS. This means that substantially a rectangu lar outlineispresented for bricking-around the same, as will be understood fromFigure 5, so that the inner fire b ick in n -0 m e d ound t e s ate haci tyhs Qa a a r i ak, :2. how n u e 5 may. b ordinary brick, or, insome installations, fire brick. The walls rest on a concrete foundation,

Another representative type of installation is shown in Figure 7 whereina cylindrical incinerator is formed either by reinforced. concrete, or,as in Figure 7, by the steel drum 36. Again, the fire brick lining 38can be laid around the grate with a minimum of time because of. itsrectangular outline in front elevation. The grate may be fastened inplace in this application by a pair of J-bolts 40 having their hooksengaged in one of the front openthe outer surface of, drum 36. The rearedge 12 of the grate lying in a plane normal to parallel side walls 29,22, grate 10 will fit snugly against a cylindrical surface such as drum36. This is because the rear edges of side walls 20, 22 lie on lines ofgeneration of'the cylinder. Almost no other shape of grate will conformto the inner wall of the drum and it is advantageous to have this easyand snug fitting to the cylindrical incinerators which are so oftenused.

The front wall 50 of grate 10 has a series of superposed openings52'extending from a location spaced from bottom edge 24 to adjacent topwall 26. When considerable consumed material has piled on the floor ofthe incinerator some of the lower openings may be blocked, and in orderto provide some openings that will always be free and also to provide asource of air to gases as they ascend from burning material, it isdesirable to have a number of these openings. Eight openings 52 havebeen shown in the grate illustrated in the drawings and six may be takenas a minimum number for efficient operation of the grate inincinerators. As indicated in Figure 8, it

may be desirable in some installations to increase the number ofopenings beyond eight. The vertical height of openings 52 is increasedfrom bottom to top of the series. This is desirable for several reasons.First it means that if lower openings are covered because of the levelof ashes in the incinerator, the effective total area of openings 52will be reduced less than if the openings were of equal size.Furthermore, the lower openings nearest to the source of air, such asducts 54, 56 in Figures and 7 respectively, will be less likely tostarve the openings 52 above. Air enters ducts 54, 56 because of thenegative pressure created by combustion in the incinerator chamber 58;and the entering air stream will have considerable velocity andpressure, at least at the lower openings. Ducts 54, 56 should be greaterin area than the total area of openings 52 appearing on the face ofgrate 10. As shown in Figure 5, the uppermost edge of the duct should beslightly below the upper edge of the solid lower portion of the frontwall 50 so that the duct does not feed directly to the lower openings.

Front wall 50 forms webs 60 between openings 52 and webs 60 extendinwardly forming flanges 62 which terminate in centrally rearwardlyopened recesses 64. Recesses 64 have contours similar in plan to thecontour of the walls of grate 10. The recesses decrease in size frombottom to top of the series of webs 60. This, in effect, decreases thearea of the vertical air passageway in grate having a funneling actionmaintaining a high pressure of the air from bottom to top, even thoughair escapes through each opening 52. Fanges 62 lap side walls 20, 22 andhave integral connection therewith. Webs 60 are relieved at their upperforward and lower rearward edges as shown in Figure 2.

The outer edges of webs 60 are superposed forming a vertically alignedbank providing no recess or inclined surface outside of openings 52 onwhich ashes would have any tendency to rest. A less precipitous frontface would tend to collect ashes and would form a surface on whichdebris could build, whereby the openings 52 could be partially covered,reducing the efliciency of the grate. The vertical front wall 50 therebyadds to the efliciency of the grate so that there will be a minimumtendency to cover the openings. As in many installations the incineratoris not tended like a furnace by frequently removing ashes or bycarefully loading the same to prevent the fuel from covering the grate,it is quite important to take every measure to prevent blocking ofopenings 52.

In large incinerators it may be desirable to use two or more grates asshown in Figure 5 and in incinterators of large capacity andconsiderable height, grates may be superposed as shown in Figure 8. Foreconomical manufacture, without having to make completely new molds fortaller grates, the construction of Figure 8 has been devised, workingwith the usual pattern for one of the grate sizes. The mold is changedon the lower grate 70 by blanking off the two lower openings 52 whichwould normally appear and providing an opening 72 in top wall 26. Uppergrate 74 is formed by reproducing grate 19 from a location immediatelybelow lowermost opening 52 to the top of the grate. As shown in Figure9, the abutting portions of the grates have a plurality of bead welds 76securing them together.

This grate has proved to be very eflicient in operation, economical ofmanufacture and installation, and adaptable to various types ofincinerator installations. The usual incinerator owner wants anincinerator that will operate with infrequent cleaning of ashes andwhich will operate although loaded to the top with debris, andincinerators with the present grate have met these demands. I do notwish to be limited to the exact details of construction shown in thedrawings, but Wish to cover those modifications within the scope of theinvention which may occur to those skilled in the art, as defined by theappended claims.

I claim:

1. A vertical grate for incinerators, comprising: a hollow cast ironbody molded as one piece, the front wall of said body beingsubstantially hemi-cylindrical and merging into substantially parallelflat vertical side walls,

the body having an open bottom and an open back and the edges of thebody at the bottom and back lying in planes normal to said side Wallsand to each other, the body having a top wall lying in a plane normal tosaid side walls, the inner surfaces of the side walls flaring to theback edges to facilitate removal of the mold, approximately the lowerthird of said front wall being solid and of uniform thickness and saidbody having a series of at least six superposed openings spaced apart upand down the remainder of said front wall, said openings beingunobstructed and being horizontally elongated to extend substantiallyfrom one side wall to the other side wall, said openings beingvertically broader and of increasing effective area from bottom to topof the series, the portions of the front wall separating the openingsbeing in the form of integral webs inwardly extending beyond theinterior surface of the lower one-third of the front wall formingflanges instanding into said hollow body, the inner margins of saidflanges forming coaxial rearwardly open recesses having substantiallysemi-circular contours, the recesses decreasing in horizontal area frombottom to top of the series of recesses.

2. A vertical grate for incinerators, comprising: a hollow cast ironbody molded as one piece, the front wall of said body beingsubstantially hemi-cylindrical and merging into substantially parallelflat vertical side walls, the body having an open bottom and an openback and the edges of the body at the bottom and back lying in planesnormal to said side walls and to each other, the body having a top walllying in a plane normal to said side walls, approximately the lowerthird of said front wall being solid and of uniform thickness and saidbody having a series of at least six superposed openings spaced apart upand down the remainder of said front wall, said openings beingunobstructed and being horizontally elongated to extend substantiallyfrom one side wall to the other'side wall, the portions of the frontwall separating the openings being in the form of integral webs, saidopenings being vertically broader and of increasing effective area frombottom to top of the series.

References Cited in the file of this patent UNITED STATES PATENTS 45,948Marshall Jan. 17, 1865 1,097,692 Weaver May 26, 1914 1,428,782 JouclardSept. 12, 1922 2,070,894 Gorsuch Feb. 16, 1937 2,565,241 Kyger Aug. 21,1951 2,625,894 Poor Jan. 20, 1953

